Pest control hub

What does it look like?

Monkey musk is a soft herb that grows up to 60cm tall, forming bright-green leafy clumps or large masses. It has thick stems that are occasionally branched. The oval leaves are opposite, up to 12 x 8cm long, usually hairless, and bright green with toothed edges. Monkey musk has yellow flowers with red spots on the bearded lower lip. Seed capsules are 1cm long, with many patterned seeds.

Monkey musk is a wetland plant. It grows along the margins of streams, rivers, drains, lakes and wetlands but it can also grow partially submerged in water, with its foliage floating on the water surface. It will also occur on damp, disturbed ground away from wetlands. Due to its relatively high light demand, it is out-competed by taller perennial or woody plants.

Why is it a problem?

Monkey musk can significantly alter the structure of riparian plant communities. It may out-compete native plants and has the potential to choke channels and impede drainage.

Monkey musk readily breaks in fast-flowing water and even small fragments have high survival, regeneration and colonisation rates. It produces large numbers of small seeds, which germinate readily both in water and on land. Monkey musk can become dominant in an area and spread widely due to its ability to propagate from both plant fragments and seed, and for both of these methods to occur at different times during the year.

Control Methods

Physical control

Hand remove all rooted plants, dry and burn.

Herbicide control

Spray with 100ml glyphosate (360g/l) + penetrant per 10L water.

Followup twice yearly late spring and late summer to ensure no seeding occurs.

CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and safety requirements are followed.

Eradication plants are present in low numbers or have a limited distribution within Northland, and eradicating them appears to be feasible and cost-effective. These pests all have the potential to establish widely in the region, and are capable of causing adverse effects to the environmental, economic, social or cultural values of the region. Council is either the lead agency or a partner for eradicating these pests from the region.

Under Section 52 and 53 of the Biosecurity Act 1993 no person can sell, propagate, breed, distribute or otherwise spread any pest in this Plan, or unwanted organism. Not complying with Section 52 or 53 is an offence under the Act, and may result in penalties noted Section 157(1).

Every person who sees, or suspects the presence of, any eradication plant shall immediately report the sighting to Northland Regional Council.

No person shall possess any eradication plant (including any seeds or live vegetation) within Northland.

What is council doing about this?

If you suspect the presence of Monkey musk please contact the Northland Regional Council immediately. Specialised control methods are required to manage this pest and will be carried out free of charge by a Biosecurity Officer or approved contractor.